I am making a spoilboard out of MDF and my z axis keeps getting off on the first hole. The small bolt that ensures the gear isn’t slipping doesn’t appear to be the problem because when it jumps, the belt gets a little loose and the gear still turns correctly.
It looks like the belt is becoming loose enough during downward pressure that the belt jumps a gear. Only if I have it lower extremely slow does it cut enough that it doesn’t skip.
Is this a bad or loose belt? Is there a way to tighten that one, or replacement only?
The one picture with the belt very loose is with the bit pressed up against some wood. That is how it looks for a split second before it jumps. The wires are just for additional grounding.
That is the newer summer 2016 edition w/ the bent plates.
Check that the M4 Z-axis tensioning bolt securely in place and adjusted so as to keep the belt guitar string tight as described in the assembly instructions:
I noticed the set screw behind the router. I’m guessing tightening that will help but do the belts also go bad other than breaking? Are there high quality low quality belts?
Make sure you’re not over-traveling the Z axis off the rails when it goes down. If it falls off the bottom and back on it can skip steps.
If you’re at the bottom of travel sometimes the 2 springs can overpower the stepper and cause it to skip steps. I always ran my S3 with one Z spring when I had the belt Z axis.
Some folks have reported good success which justifies the extra expense of purchase genuine Gates-branded GT2 2mm pitch belts (6mm wide endless for Z, 9mm wide in suitable lengths for XY).
Removing the spring as noted by @SLCJedi is a technique some customers have used.
